Unit 3: Network Services
Networking · Unit 3 · Paper 3

Network Services unit test

A test on this unit alone, marked as a percentage and a letter grade — for the test your class is actually sitting, rather than for May. Answer everything, then submit once: seeing the answer to question 3 before attempting question 4 makes the final percentage meaningless.

Each paper is built from this unit’s 40 terms and is the same for everyone, so a teacher can assign “Unit 3, Paper 3” and every student sits the identical test. Multiple choice is marked objectively; the written sections you mark yourself against the model answer and rubric.
Suggested time 33 min 30 points0/17 attempted
1

DHCP

2

Well-known ports 22, 23, 25

3

SSH

4

NS record

5

DHCP lease

6

SMTP, POP3 and IMAP

7

Authoritative vs recursive DNS server

8

PTR record

9

Proxy server

10

CNAME record

11

Reverse proxy

12

Certificate and TLS handshake

Short answer 1. Define or explain: NTP

3 pts

Short answer 2. Define or explain: DHCP reservation

3 pts

Short answer 3. Define or explain: SNMP

3 pts

Short answer 4. Define or explain: Well-known ports 161, 389, 443, 3389

3 pts

Free response

6 pts

A student types a web address into a browser on a laptop that has just joined a campus Wi-Fi network, and a page loads. (a) Describe what DHCP does for the laptop when it joins, and name two pieces of configuration it receives beyond its own IP address. (b) Describe how the domain name is resolved to an IP address, including what happens when the local resolver has no cached answer. (c) Explain encapsulation by describing what is added to the data as it moves down the sending host's stack. (d) The page fails to load but the student can reach a site by typing its IP address directly. State what this isolates as the likely fault and explain your reasoning.